Field of the Invention
Embodiments of the invention relate to the manufacturing field of a semiconductor apparatus, and more particularly, to a chamber.
Description of the Related Art
in the process of semiconductor manufacturing, a degas chamber is used for heating a wafer, such that foreign matters adhering to the wafer, such as organics and moisture, are volatilized, and the purpose of cleaning the wafer is thus realized.
Typically, a current structure of a degas chamber is as shown in FIGS. 1 and 2, in which a quartz window 3 is provided between a chamber 1 and infrared heat lamps 2 for the purpose of isolation and ensuring the tightness of the chamber 1. A resin pad 4 is provided above a. side wall 6 of the chamber 1, and the resin pad 4 and the side wall 6 of the chamber 1 together form a recess for accommodating the quartz window 3. The recess is not only used for restricting the movement of the quartz window 3 in a horizontal direction, but also used for supporting the quartz window 3. Generally, the inside of the chamber 1 is under a vacuum condition, and gas is introduced into the chamber 1 after a wafer is transferred from the outside of the chamber onto a heater 5, such that the pressure in the chamber 1 is about 10 torr. After that, the wafer is heated so as to remove foreign matters, and when the heating is finished, the gas in the chamber 1 is evacuated, resulting in that the inside of the chamber 1 is under the vacuum condition again.
During above gas introduction and evacuation processes, the quartz window 3 repeatedly bears an alternating pressure due to the variation in pressure inside the chamber 1. Since the quartz window 3 of the above current structure is not fixed in a vertical direction, but only supported by the resin pad 4, the quartz window 3 may move in the vertical direction under the action of the alternating pressure. Particularly, during the evacuation process, due to the atmospheric pressure above the chamber, the quartz window 3 bears a relatively large downward pressure, which is then transferred to the resin pad 4, and the resin pad 4 deforms when subject to the downward pressure transferred from the quartz window 3, resulting in that the quartz window 3 moves downward. The deformation of the resin pad 4 being pressed is relatively large due to its relatively low hardness, generally resulting in that an upper surface thereof becomes not higher than an upper surface of the side wall 6 of the chamber 1 at the inner side of the resin pad 4, and in this case, a collision occurs between the quartz window 3 and the side wall 6 of the chamber 1, which leads to a breakage of the quartz window 3. Meanwhile, during the heating process, a temperature of the quartz window 3 is increased and heat is conducted to the resin pad 4, which may soften and deform the resin pad 4, so that the quartz window 3 will be subject to an uneven force, by which the quartz window 3 is more likely to be broken.
To prevent the quartz window from colliding with the chamber and thus being broken, there is also provided a degas chamber in the conventional art, which has a quartz window fixing device. As shown in FIG. 3, on basis of the above structure of degas chamber, this degas chamber further includes a fixing device including a quartz window press ring 8, a press ring bumper 9 and a resin pad 4. The quartz window press ring 8 is fixedly mounted on the side wall 6 of the chamber, and the mounted quartz window press ring 8 is pressed against an upper surface of the quartz window 3 so as to apply a preload onto the quartz window 3. The press ring bumper 9 is directly placed on the quartz window 3 and is fixed by the preload from the quartz window press ring 8. The degas chamber having the quartz window fixing device is capable of confining the moving space of the quartz window 3 in the vertical direction to a certain extent when the pressure in the chamber varies, and thus preventing the quartz window 3 from frequently colliding with the chamber in the manufacturing process, thereby realizing a protection effect for the quartz window 3.
The above degas Chamber having the quartz window fixing device is capable of reducing the moving space of the quartz window to a certain extent and thus lowering the force of collision between the quartz window and the chamber, but, since the quartz window is still supported by the resin pad, the resin pad is inevitably deformed due to the pressure in the repeated gas introduction and evacuation processes, and is inevitably deformed due to the heat in the heating process, and therefore, the damage to the quartz window caused by the side wall of the chamber cannot be fundamentally avoided.